1. Field of the Invention
The present invention relates to a disk recording device for recording data onto a disk using an optical beam emitted from an optical head, and in particular to a disk recording device of which recording speed is set at a recording speed at which recording data can be recorded onto a disk in use, so as to accommodate differences in recording properties among disks.
2. Description of the Related Art
CD-R (compact disk recordable) and CD-RW (compact disk rewritable) systems are well known systems in which an optical beam from an optical head is used for recording digital data onto a disk. Efforts are constantly being made to increase the recording speeds of these disk recording devices.
Current state of the art CD-R drives are able to record data at a recording speed eight (8xc3x97) to twelve (12xc3x97) times their standard speed. Current state of the art CD-RW drives can record data at a recording speed twice (2xc3x97) or four times (4xc3x97) their standard speed.
Disks for use in recording by such disk recording devices differ in material composition depending on manufacturers or adaptable speed grades, and thus different types of disks exhibit different recording properties such as sensitivity, frequency characteristics, and so on.
In disk recording devices, an emission output issued from an optical head is set at an optimum recording level for disk recording according to a recording speed which is set when recording. Alternatively, an emission output issued from an optical head when recording is set at an optimum recording level for compensation of a difference in disk recording properties.
Such setting of an emission output from an optical head at an optimum recording level is achieved through trial writing into an emission output setting calibration area while gradually varying the emission output, the calibration area being provided in a disk separately from the program area where actual recording data is to be recorded.
During recording, the reflection level of a recording pulse is detected as data is recorded onto a disk using an emission output set at an optimum recording level through the trial writing, and the emission output is further corrected according to the detected reflection level, whereby the emission output for actual data recording is adjusted to a more optimum recording level.
Here, even though an emission output from an optical head is set at an optimum recording level for disk recording, as described above, when an inferior disk is used, recording data may not be properly recorded. Moreover, an ATIP address for absolute time information in ATIP (absolute time in pre-groove) may not be restored from a wobble signal extracted from a pre-groove of a disk. This may disrupt the recording.
Recording may also be disrupted when actual recording speed deviates significantly from a disk""s adaptable recording speed.
According to the present invention, when recording conditions are inferior, a recording speed is corrected stepwisely until a recording speed allowing proper disk recording is set. With this arrangement, when a disk recording condition is inferior, the recording is discontinued to prevent recording failure.